This guide will help you to Install nginx 1.6 php5.4 mysql 5.5 on Centos 6 so read carefully this article for the same.
First we need to install nginx 1.6 repository using below command:
rpm -Uvh http://nginx.org/packages/centos/6/noarch/RPMS/nginx-release-centos-6-0.el6.ngx.noarch.rpm
Install nginx web-server
yum install nginx
## Installing mysql 5.5
First Install remi repository
rpm -Uvh http://rpms.famillecollet.com/enterprise/remi-release-6.rpm
OR
Create a new repository file as below:
vi /etc/yum.repos.d/nginx.repo
Now enter the following content in the file
[nginx]
name=nginx repo
baseurl=http://nginx.org/packages/centos/$releasever/$basearch/
gpgcheck=0
enabled=1
name=nginx repo
baseurl=http://nginx.org/packages/centos/$releasever/$basearch/
gpgcheck=0
enabled=1
Now install mysql 5.5 using following command:
yum –enablerepo=remi install mysql mysql-server
## Installing PHP 5.4
yum –enablerepo=remi install php php-common php-mysql php-pgsql php-pecl-mongo php-sqlite php-pecl-memcache php-pecl-memcached php-gd php-mbstring php-mcrypt php-xml php-pecl-apc php-cli php-pear php-pdo
## Installing PHP 5.5
rpm -Uvh http://mirror.webtatic.com/yum/el6/latest.rpm
yum install php55w php55w-gd php55w-imap php55w-mbstring php55w-soap php55w-mcrypt php55w-pear

Great post!!! thank you